apache maxclients limit

maxclients.pl

use strict;
use warnings;
use Linux::Smaps;
use List::Util; # not core module

@ARGV or die "usage: %0 [pid...]";

my $memory_total = `cat /proc/meminfo | grep MemTotal | awk '{print \$2}'` * 0.7; # -30% memory total
my @shared;
my @rss;

print "PID\tRSS\tSHARED\t\n";

for (@ARGV) {
    my $map = Linux::Smaps->new($_);
    unless ($map) {
        warn "not exists process...: $!";
        next;   
    }   
    push @shared, ($map->shared_dirty + $map->shared_clean);
    push @rss, $map->rss;
    printf "%d\t%d\t%d (%d%%)\n", $_, $map->rss, $map->shared_dirty + $map->shared_clean, int((($map->shared_dirty + $map->shared_clean) / $map->rss) * 100);
}

my $avg_shared = List::Util::sum(@shared) / scalar(@shared);
my $avg_rss = List::Util::sum(@rss) / scalar(@rss);
my $maxclient = scalar($memory_total / ($avg_rss + $avg_shared));

print "------ MaxClients -----------\n";
printf "memory_total / (avg_rss + avg_shared) = %dKB / (%dKB + %dKB) = %d\n", $memory_total, $avg_rss, $avg_shared, $maxclient;
print "-----------------------------\n";

# vim ts=4